Subframe processing method and device

ABSTRACT

A subframe processing method and device are disclosed. The subframe processing method includes: if data packets that are not received by an evolved NodeB (eNB) include at least two consecutive Multimedia Broadcast Multicast Service (MBMS) data packets to be scheduled in a Dynamic Schedule Period (DSP) by the eNB, setting a subframe of the eNB that is used to transmit Dynamic Schedule Information (DSI) corresponding to the DSP to null. When the eNB finds that consecutive MBMS data packets are lost and/or that a type 0 Protocol Data Unit (PDU) group is lost, a subframe used to transmit the DSI may be set to null, thereby preventing the eNB from transmitting incorrect DSI which may interfere with other eNBs and cause incorrect data receiving of a user equipment (UE).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/433,876, filed on Mar. 29, 2012, which is a continuation ofInternational Application No. PCT/CN2010/077371, filed on Sep. 27, 2010.The International Application claims priority to Chinese PatentApplication No. 200910110717.0, filed on Sep. 29, 2009. All of theaforementioned patent applications are hereby incorporated by referencein their entireties.

FIELD OF THE INVENTION

The present invention relates to the field of mobile communicationstechnologies, and in particular, to a subframe processing method anddevice.

BACKGROUND OF THE INVENTION

In a long term evolution (LTE) system, Multimedia Broadcast MulticastService (MBMS) data may be transmitted in MBMS Single Frequency Network(MBSFN) mode. That is, multiple evolved NodeBs (eNBs) transmit radiosignals carrying the same MBMS data with the same frequency at the sametime from multiple cells. An area covered by the multiple eNBs thattransmit the MBMS data in MBSFN mode is called an MBSFN area. Userequipments (UEs) in the MBSFN area may consider that only onetransmitter is transmitting radio signals and receive the MBMS data.

Data transmitted by the eNBs in the MBSFN area is the same, and thephysical resources used are the same. That is, information of each eNBis synchronous. For example, a synchronization (SYNC) entity is set onthe broadcast multicast-service center (BM-SC) side on the core network(CN) and an SYNC entity is set on the eNB side. The SYNC entity on theBS-SC side sets a time stamp for various MBMS data packets and providesthe time stamp for all eNBs in the MBSFN area. Specifically, the BM-SCmay include multiple MBMS data packets in a synchronization sequence.The SYNC entity on the BM-SC side sets the same time stamp for MBMS datapackets in a synchronization sequence and transmits a type 0 controlpacket (namely, a type 0 Protocol Data Unit (PDU), hereinafter referredto as a type 0 PDU) after the BM-SC transmits the synchronizationsequence. The type 0 PDU is used to notify the eNBs of transmissioncompletion of the current synchronization sequence. To improve thereliability, the SYNC entity on the BM-SC side transmits a type 0 PDUgroup but not merely a type 0 PDU. The type 0 PDU group includes alltype 0 PDUs that include the same information and are transmittedrepeatedly. For example, after a synchronization sequence istransmitted, a type 0 PDU is transmitted consecutive three times. Thethree type 0 PDUs form one type 0 PDU group.

When receiving the MBMS data, eNB determines the time when the BM-SCstarts to transmit the synchronization sequence according to the timestamp obtained by the SYNC entity on the eNB side, and determinesreception completion of the synchronization sequence according to thetype 0 PDU. The eNB transmits the received MBMS data packets accordingto the time stamp of the received MBMS data packets.

If the eNBs in the MBSFN area have buffered all MBMS data packets to betransmitted in a Dynamic Schedule Period (DSP) before the DSP, the eNBscan generate the same Dynamic Schedule Information (DSI) to implementthe same dynamic scheduling for the same MBMS data packets. For example,the eNBs have buffered all the MBMS data packets to be transmitted inthe DSP before the DSP. The eNBs determine the time for transmitting theMBMS data packets, and then generate DSI corresponding to the DSP toindicate scheduling of the DSP, for example, the start positions of datapackets of different services in the DSP. In a first MBSFN subframe on amulticast channel (MCH), the eNBs transmit the DSI of the correspondingtransmission channel in the DSP and transmit the data packets accordingto the scheduling result. A UE at the receiving end receives the DSI,knows eNB scheduling according to the DSI, and thus selects the timewhen the eNBs transmit data that is interesting to the UE to receivedata.

In evolved MBMS, air interface resources of the MBSFN service arereserved in advance in a manner of semi-persistent scheduling. Areserved subframe that is used to transmit MBSN data is called an MBSFNsubframe. To meet different quality of service (QoS) requirements ofdifferent MBSFN services, the evolved MBMS maps the MBSFN services todifferent MCHs, and the different MCHs adopt different Modulation CodingSchemes (MCSs) to achieve different QoS. Different MCHs do not share areserved MBSFN subframe. To reduce scheduling overheads, the eNBsperform air-interface transmission scheduling for MBMS data in each DSP.The eNBs only schedule MB SFN data of which time stamp is earlier thanthe start time of the corresponding DSP. Generally, the eNBs schedulethe corresponding MBSFN data in one DSP that is later than a time stamp.

In the prior art, transmission between a BS-SC and an eNB is based onthe Internet Protocol (IP), which may cause loss of MBMS data packets ora type 0 PDU. If an eNB in an MBSFN area cannot normally receive atleast two consecutive MBMS data packets in a synchronization sequence orall type 0 PDUs that indicate transmission completion of asynchronization sequence, the eNB generates incorrect DSI, which mayinterfere with other eNBs and cause incorrect data receiving of the UE.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide a subframe processingmethod and device.

A subframe processing method is provided, where the method includes:

-   -   if data packets that are not received by an eNB include at least        two consecutive MBMS data packets to be scheduled by the eNB in        a DSP, setting, by the eNB, a subframe that is used to transmit        DSI corresponding to the DSP to null.

Another subframe processing method is provided, where the methodincludes:

-   -   if an eNB does not receive a type 0 control packet group,        setting, by the eNB, a subframe that is used to transmit DSI        corresponding to a DSP to null, in which the DSP is used to        transmit MBMS data packets corresponding to the type 0 control        packet group.

A subframe processing device is provided, where the device includes:

-   -   a first receiving unit, configured to determine whether data        packets that are not received meet a first condition: the data        packets that are not received include at least two consecutive        MBMS data packets to be scheduled by a first sending unit in a        DSP; and    -   the first sending unit, configured to set a subframe that is        used to transmit DSI corresponding to the DSP to null when the        determination result of the first receiving unit is yes.

Another subframe processing device is provided, where the deviceincludes:

-   -   a second receiving unit, configured to determine that a type 0        control packet group is not received; and    -   a second sending unit, configured to set a subframe that is used        to transmit DSI corresponding to a DSP to null when the        determination result of the second receiving unit is yes, in        which the DSP is used to transmit MBMS data packets        corresponding to the type 0 control packet group.

In embodiments of the present invention, when an access network (AN)device (such as an eNB) finds that consecutive MBMS data packets arelost and/or a type 0 PDU group is lost, a subframe that is used totransmit DSI may be null to prevent the eNB from transmitting incorrectDSI which may interfere with other eNBs and cause incorrect datareceiving of a UE.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic flow chart of a subframe processing methodaccording to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a synchronization sequence transmittedby a BM-SC according to an embodiment of the present invention;

FIG. 3 is a schematic flow chart of another subframe processing methodaccording to an embodiment of the present invention;

FIG. 4 is a schematic diagram of another synchronization sequencetransmitted by a BM-SC according to an embodiment of the presentinvention;

FIG. 5 is a schematic diagram of a subframe processing device accordingto an embodiment of the present invention; and

FIG. 6 is a schematic diagram of another subframe processing deviceaccording to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The technical solution of the present invention will be clearly andcompletely described in the following with reference to the accompanyingdrawings. It is obvious that the embodiments to be described below areonly a part rather than all the embodiments of the present invention.All other embodiments obtained by persons or ordinary skill in the artbased on the embodiments of the present invention without any creativeeffort shall fall within the protection scope of the present invention.

An embodiment of the present invention provides a subframe processingmethod. According to the method, if data packets that are not receivedby an eNB include at least two consecutive MBMS data packets to bescheduled by the eNB in a DSP, the eNB sets a subframe that is used totransmit DSI corresponding to the DSP to null to prevent the eNB fromtransmitting incorrect DSI which may interfere with other eNBs and causeincorrect data receiving of a UE.

Another embodiment of the present invention provides a subframeprocessing method, as shown in FIG. 1. An eNB is located in an AN; aBM-SC is located in a CN; an SYNC entity on the BM-SC side may be anindependent entity that is located on the CN and is able to communicatewith the BM-SC, a part of the independent entity, or a unit inside aBM-SC device. The method includes the following steps.

Step 110: The BM-SC transmits MBMS data packets to the eNB.

For example, the BM-SC transmits a synchronization sequence, whichincludes multiple MBMS data packets, to the eNB. Generally, MBMS datapackets in one synchronization sequence belong to one MBMS service.Besides, MBMS data packets in one synchronization sequence may belong tomultiple MBMS services. The SYNC entity on the BM-SC side sets the sametime stamp for each MBMS data packet in the synchronization sequence,and then transmits a type 0 PDU after the BM-SC transmits all MBMS datapackets in the synchronization sequence.

Further, header information of the MBMS data packets may include a“total number of octet”, which indicates the total amount of datatransmitted by a data source in a certain period of time. Similar to theprior art, the value of the field of “total number of octet”monotonically increases in a certain time for data of a service. Theheader information of the MBMS data packets may further include a “totalnumber of packet”, which indicates the total amount of packetstransmitted by a data source in a certain period of time. The datasource refers to the BM-SC in this embodiment.

As shown in FIG. 2, assume that four consecutive MBMS data packetstransmitted by the BM-SC to the eNB are A, B, C, and D. Lengths of A, B,C, and D are 100 bytes, 50 bytes, 150 bytes, and 100 bytes respectively.The values of the “total number of octet” information in the headers ofthe corresponding data packets are 100 bytes, 150 bytes, 300 bytes, and400 bytes respectively. For example, the value of the “total number ofoctet” in the header of D indicates the total number of octets of D andthe previous MBMS data packets, namely, 400 (100+50+150+100=400) bytes.Header information of A, B, C, and D further include total number ofpacket information (not shown in FIG. 2), of which values are 1, 2, 3,and 4 respectively. For example, the value of the total number of packetin the header of D indicates the total number of packets, which includeD and the previous MBMS data packets, that are transmitted by the BM-SC,namely, 4.

Step 120: The eNB receives the MBMS data packets that are transmitted bythe BM-SC, and determines whether the following case occurs: at leasttwo consecutive MBMS data packets to be scheduled in a DSP are lost. Ifat least two consecutive MBMS data packets to be scheduled in a DSP arelost, the process proceeds to step 130; and if not at least twoconsecutive MBMS data packets to be scheduled in a DSP are lost, theprocess proceeds to step 140.

The preceding case determined by the eNB whether occurs may also bedescribed as follows. At least two consecutive MBMS data packets to bescheduled in a DSP do not reach the eNB, that is, at least twoconsecutive MBMS data packets to be scheduled in a DSP are not receivedby the eNB.

For example, according to SYNC header information of the received MBMSdata packets, the eNB determines whether consecutive data packets arelost and whether the consecutively lost data packets are supposed to bescheduled in the same DSP. The eNB may implement the operation accordingto the prior art.

As shown in FIG. 2, assume that two consecutive DSPs in which the eNBschedules MBMS data packets are DSP1 and DSP2 respectively. The starttime of DSP1 is T1, and the start time of DSP2 that is later than DSP1is T2. MBMS data packets shown in FIG. 2 are included in asynchronization sequence, that is, the MBMS data packets have the sametime stamp. Assume that the time indicated in the time stamp is T0. Instep 120, if the eNB determines that T0 is between T1 and T2, that is,T0 is later than T1 and earlier than T2, the eNB determines that itshould schedule the MBMS data packets A, B, C, and D in DSP2.

Further, assume that the eNB receives only A and D, the eNB can buffer Aand D. According to the total number of octets 100 in the header of A,total number of octets 400 in the header of D, and data packet length100 of D, the eNB may determine that MBMS data of 200 (400−100−100=200)bytes is the lost data that should have been received by the eNB butdoes not reach the eNB. According to the total number of packets 1 inthe header of A and the total number of packets 4 in the header of D,the eNB may determine that two MBMS data packets with the total numberof packets 2 and 3 in the headers exist between A and D. Through thepreceding process, the eNB may determine that two consecutive MBMS datapackets (B and C) are lost. It should be noted that the eNB can onlydetermine loss of data packets and the number of the lost data packets,and cannot determine the length of each lost data packet. Therefore, ifthe eNB predicts the length of each MBMS data packet and generates DSIaccording to the prior art, the DSI may be incorrect and may bedifferent from DSI generated by other eNBs in other MBSFN areas.Consequently, the incorrect DSI interferes with other eNBs, and a UE mayincorrectly receive data or even cannot receive data.

In the preceding process, according to the SYNC header information ofthe received MBMS data packets, the eNB determines that consecutive datapackets are lost and the MBMS data packets that are not received aresupposed to be scheduled in a DSP. The process proceeds to step 130.

Step 130: The eNB sets a subframe that is used to transmit DSIcorresponding to the DSP to null.

For example, the eNB keeps mute in a subframe, the subframe beingsupposed to be used to transmit the DSI corresponding to the DSP. Foranother example, the eNB first determines whether to generate completeDSI corresponding to the DSP, and if it is determined not to generatethe complete DSI corresponding to the DSP, the eNB keeps mute in asubframe, the subframe being supposed to be used to transmit the DSIcorresponding to the DSP.

This step in which the eNB sets a subframe that is used to transmit theDSI corresponding to the DSP to null may also be described as follows.The eNB does not transmit any information when the eNB should transmit asubframe that carries the DSI. The DSI that should be generated is usedto instruct the eNB how to dynamically schedule the MBMS data that issupposed to be transmitted in the DSP.

It should be noted that a subframe that is supposed to be used totransmit the DSI corresponding to a DSP in the embodiment of the presentinvention refers to a subframe X in a DSP (for example, a first subframein a DSP). If the eNB generates DSI, the eNB is to transmit the DSI inthe subframe X. In the embodiment of the present invention, the eNB doesnot generate DSI when the eNB determines that the data packets that arenot received meet a given condition (for example, step 120). Therefore,the eNB keeps mute in the subframe X.

In this step, the eNB may transmit the MBMS data packets in the DSP. Indetails, if other MBMS data packets that have been received by the eNBand are to be scheduled in the DSP exist, the eNB may transmit the otherMBMS data packets in other subframes in the DSP. Optionally, if asubframe that is supposed to be used to transmit the DSI correspondingto the DSP is the first subframe of the DSP, the other subframes may beafter the subframe that is supposed to be used to transmit the DSIcorresponding to the DSP. If a subframe that is supposed to be used totransmit the DSI corresponding to the DSP is not the first subframe ofthe DSP, the other subframes may be before or after the subframe that issupposed to be used to transmit the DSI corresponding to the DSP.Optionally, other MBMS data packets may include: MBMS data packets ofwhich time of transmission by the BM-SC is earlier than the time oftransmission of the determined lost consecutive MBMS data packets by theBM-SC, and which belong to the same service as the determined lostconsecutive MBMS data packets; and/or MBMS data packets of otherservices that are supposed to be scheduled before the eNB schedules aservice of the determined lost consecutive MBMS data packets. In thelatter case, the other MBMS data packets belong to a service differentfrom that of the lost consecutive MBMS data packets. The time oftransmission of the other MBMS data packets by the BM-SC may not beearlier than the time of transmission of the determined lost consecutiveMBMS data packets by the BM-SC.

As shown in FIG. 2, the eNB has received A in step 120. According toheader information of the received MBMS data packets, the eNB can knowthat the time when the BM-SC transmits A is earlier than the time whenthe BM-SC transmits the lost consecutive data packets (B and C). Inaddition, the eNB has also received D. The time when the BM-SC transmitsD is later than the time when the BM-SC transmits the lost consecutivedata packets. Therefore, in the DSP, the eNB can use a subframe after anull subframe that is supposed to be used to transmit the DSI totransmit A. The eNB can only determine the number and the total lengthof the lost data packets, but cannot determine the length of each lostdata packet (B and C). Therefore, the eNB cannot determine thetransmission position of each lost data packet and cannot determine thetransmission position of D that is transmitted later than the lost datapackets. As a result, the eNB cannot transmit D even when the eNB hasreceived D.

Assume that the eNB transmits A in a manner of dynamic schedulingaccording to the prior art. Accordingly, a UE can read all informationin the DSP when the UE does not receive the DSI corresponding to theDSP. The UE can read MBMS data packet A. Compared with the method inwhich the eNB transmits no data packet or transmits incorrect DSI, themethod according to this embodiment enables the UE to receive more data,and enables the eNB to transmit data more efficiently.

Optionally, assume that the DSP includes a subframe being supposed to beused to transmit the DSI, other subframes that are used to transmit theother MBMS data packets, and remaining subframes, the eNB may keep mutein the remaining subframes after transmitting the other MBMS datapackets in the DSP. It should be noted that the subframes that form theDSP are subframes of an MCH reserved by the eNB for transmitting theMBMS data packets, and “the eNB keeps mute in the remaining subframes ofthe DSP” means that the eNB does not transmit any information on an MCHthat is used to transmit MBMS data packets in the remaining subframes.

It is understandable by persons of ordinary skill in the art that theeNB may transmit non-MBMS data packets in the remaining subframes. Thesenon-MBMS data packets occupy non-MCHs. For example, the eNB may transmitunicast data packets at low power in the remaining subframes. Theseunicast data packets are carried on a dedicated traffic channel (DTCH).The occupied transmission channel is a downlink shared channel (DL-SCH).

Step 140: The eNB generates and transmits the DSI corresponding to theDSP.

In this step, the eNB can generate and transmit the DSI according to theprior art. After transmitting a subframe that carries the DSI, the eNBtransmits the received MBMS data packets.

In this embodiment, the eNB may first determine whether data packetsthat are not received meet a given condition. For example, the eNBdetermines whether the data packets that are not received include atleast two consecutive MBMS data packets to be scheduled by the eNB in aDSP. If the given condition is met, the eNB sets a subframe that is usedto transmit DSI corresponding to the DSP to null to prevent the eNB fromtransmitting incorrect DSI which may interfere with other eNBs and causeincorrect data receiving of the UE.

Another embodiment of the present invention provides a subframeprocessing method. In this method, if an eNB does not receive a type 0control packet group, that is, data packets that are not received by theeNB include a type 0 control packet group, the eNB sets a subframe thatis used to transmit DSI corresponding to a DSP to null. The DSP is usedto transmit MBMS data packets corresponding to the type 0 control packetgroup. This method can prevent the eNB from transmitting incorrect DSIwhich may interfere with other eNBs and cause incorrect data receivingof a UE.

Another embodiment of the present invention provides a subframeprocessing method, as shown in FIG. 3. An eNB is located on an AN; aBM-SC is located on a CN; an SYNC entity on the BM-SC side may be anindependent entity that is located on the CN and can communicate withthe BM-SC, a part of the independent entity, or a unit inside a BM-SCdevice. The method includes the following steps.

Step 310: The BM-SC transmits a synchronization sequence formed of MBMSdata packets and the corresponding type 0 PDU group to the eNB.

As shown in FIG. 4, the BM-SC transmits four synchronization sequencesE, F, G, and H to the eNB. Each synchronization sequence includesseveral MBMS data packets. The number of the MBMS data packets includedin each synchronization sequence may be the same or different. Thisembodiment does not restrict that the MBMS data packets in asynchronization sequence belong to one or more MBMS services. Thisembodiment does not restrict whether the MBMS data packets in asynchronization sequence are empty. For example, MBMS data packets in Gare empty, or G does not contain any MBMS data.

In this step, the SYNC entity on the BM-SC side sets a time stamp foreach MBMS data packet in each synchronization sequence. Aftertransmitting all MBMS data packets in a synchronization sequence, theBM-SC transmits a type 0 PDU group corresponding to the synchronizationsequence. Each type 0 PDU group that corresponds to a synchronizationsequence may include multiple type 0 PDUs. The type 0 PDUs may have thesame information and may have the same time stamp as the MBMS datapackets in the corresponding synchronization sequence. Type 0 PDUs thatare repeatedly transmitted by the BM-SC may form a type 0 PDU group.

As shown in FIG. 4, a type 0 PDU group corresponding to eachsynchronization sequence includes three type 0 PDUs, which are marked as1, 2, and 3 according to the sequence in each type 0 PDU group.Optionally, a type 0 PDU in a type 0 PDU group corresponding tosynchronization sequence E may carry a time stamp. The time stamp is thesame as the time stamp of the MBMS data in synchronization sequence E.Assume that the time stamp is Te. MBMS data packets in synchronizationsequence G are null, that is, G does not include MBMS data. A type 0 PDUin a type 0 PDU group corresponding to synchronization sequence G maycarry a time stamp, and the time stamp may be a value in the time rangeof synchronization sequence H. Assume that the time stamp is Tg. Inaddition, assume that the time indicated by a time stamp of MBMS datapackets in synchronization sequence F and the time indicated by a timestamp of MBMS data packets in synchronization sequence H are Tf and Threspectively. Header information of each MBMS data packet is notillustrated in FIG. 4.

Further, the header information of the MBMS data packets may furtherinclude the total number of octets and the total number of packets. Theheader information is similar to the header information in otherembodiments of the present invention, and is not described here.

Step 320: The eNB receives the synchronization sequence transmitted bythe BM-SC and determines whether the following case occurs: one type 0PDU group is lost. If one type 0 PDU group is lost, the process proceedsto step 330; and if no one type 0 PDU group is lost, the processproceeds to step 340.

The preceding case may also be described as follows. A type 0 PDU groupcorresponding to a synchronization sequence that is received or notreceived by the eNB does not reach the eNB, that is, all type 0 PDUs inthe type 0 group are not received by the eNB. A synchronization sequencemay include multiple MBMS data packets. Time stamps of MBMS data packetsin a synchronization sequence are the same, that is, multiple MBMS datapackets in a synchronization sequence correspond to a type 0 PDU group,which means, each MBMS data packet has a unique type 0 PDU group. Thepreceding case the eNB determines whether occurs may also be describedas follows. A type 0 PDU group corresponding to MBMS data packets thatare received or not received by the eNB does not reach the eNB, that is,all type 0 PDUs in the type 0 group are not received by the eNB.

It should be noted that the subframe processing method provided by thisembodiment is applicable to various scenarios where an eNB may determineloss of a type 0 PDU group. In details, if a type 0 PDU group is lost,an eNB may determine the type 0 PDU group that should reach the eNB butis not received by the eNB according to information related to thereceived MBMS data packets such as a time stamp, the total number ofoctets, or the total number of packets, regardless of whether all orpart of synchronization sequences corresponding to the type 0 PDU groupare received by the eNB, or synchronization sequences corresponding tothe type 0 PDU group are empty. Therefore, the subframe processingmethod provided by this embodiment is applicable to various scenarios.

In this embodiment, assume that two consecutive DSPs in which the eNBschedules MBMS data packets are DSP3 and DSP4 respectively. The starttime of DSP3 is T3, and the start time of DSP4 that is later than DSP3is T4.

As shown in FIG. 4, in step 320, if the eNB determines that Te, Tf, Tg,and Th are between T3 and T4, that is, Te, Tf, Tg, and Th are later thanT3 and earlier than T4, the eNB determines that the eNB should schedulethe MBMS data packets in E, F, and H in DSP4.

Further, the eNB may determine a range of time stamp in which eachsynchronization sequence is supposed to be received according to thepre-configuration. Therefore, if the eNB does not receive any type 0 PDUand the time stamp is in a range of time stamp determined according tothe pre-configuration, it is determined that a type 0 PDU group is lost.If information of at least one PDU group in the preceding four type 0PDU groups is lost, the process proceeds to step 330.

As shown in FIG. 4, the eNB does not receive a first type 0 PDU, asecond type 0 PDU, and a third type 0 PDU corresponding to F; therefore,the eNB cannot determine the time of transmission completion of datapackets in synchronization sequence F even when the eNB receivessynchronization sequence F. If the eNB predicts the time of transmissioncompletion of data packets in the synchronization sequence according tothe prior art, the time is inaccurate. Therefore, DSI generated by theeNB according to the prediction result is inaccurate, and is differentfrom DSI generated by other eNBs in other MBSFN areas. Consequently, theincorrect DSI interferes with other eNBs, and a UE may incorrectlyreceive data or even cannot receive data. In this embodiment, after theeNB determines that all information in a type 0 PDU group correspondingto F is lost, the process proceeds to step 330.

If at least one type 0 PDU in each type 0 PDU group in the precedingfour type 0 PDU groups is received by the eNB, the eNB may determine thetime of transmission completion of each synchronization sequence. Theprocess proceeds to step 340.

Step 330: The eNB sets a subframe that is used to transmit DSIcorresponding to a DSP to null. The DSP is used to transmit MBMS datapackets corresponding to a type 0 PDU group or MBMS data packets in asynchronization sequence that are not received by the eNB.

For example, the eNB keeps mute in a subframe, the subframe beingsupposed to be used to transmit DSI corresponding to the DSP. Further,for example, the eNB first determines whether to generate complete DSIcorresponding to the DSP. If it is determined not to generate thecomplete DSI corresponding to the DSP, the eNB keeps mute in a subframe,the subframe being supposed to be used to transmit the DSI correspondingto the DSP.

This step in which the eNB sets a subframe that is used to transmit DSIcorresponding to the DSP to null may also be described as follows. TheeNB does not transmit any information when the eNB should transmit asubframe that carries the DSI. The DSI that should be generated is usedto instruct the eNB how to dynamically schedule MBMS data that issupposed to be transmitted in the DSP.

In this step, the eNB may transmit MBMS data packets in the DSP. Indetails, if other MBMS data packets that have been received by the eNBand are to be scheduled in the DSP exist, the eNB may transmit the otherMBMS data packets in other subframes in the DSP. Optionally, the otherMBMS data packets may include MBMS data packets of which time oftransmission by the CN device BM-SC is earlier than the end time of asynchronization sequence corresponding to a lost type 0 PDU group;and/or MBMS data packets that are supposed to be scheduled by the eNBbefore the eNB schedules a service of MBMS data packets corresponding toa lost type 0 PDU group, and which belong to a service different fromthat of the MBMS data packets corresponding to the lost type 0 PDUgroup.

As shown in FIG. 4, the eNB has received synchronization sequence E instep 320, and MBMS data packets in E are to be scheduled in the DSP. Inaddition, according to header information of the received MBMS datapackets, the eNB can know that the time of transmission of E by theBM-SC is earlier than the time of transmission of the synchronizationsequence (F) corresponding to the lost type 0 PDU group. Therefore, inthe DSP, in subframes after the null subframe that is supposed to beused to transmit DSI, the eNB may transmit the received MBMS datapackets in synchronization sequence E. If the eNB does not receive thetype 0 PDU group corresponding to synchronization sequence F, butreceives some MBMS data packets in synchronization sequence F, the eNBmay transmit the received MBMS data packets in synchronization sequenceF after transmitting MBMS data packets in E. The eNB cannot determinewhether transmission of F is completed, so the eNB cannot determine thetransmission positions of MBMS data packets in G and H in the DSP evenwhen the eNB receives synchronization sequences G and H transmitted bythe BM-SC. Therefore, the eNB does not transmit the received MBMS datapackets in G and H. Further, assume that the eNB transmits E in a mannerof dynamic scheduling according to the prior art. Accordingly, a UE canread all information in the DSP when the UE does not receive the DSIcorresponding to the DSP. The UE can read MBMS data packets in E.Compared with the method in which the eNB transmits no data packet ortransmits incorrect DSI, the method provided by this embodiment enablesthe UE to receive more data, and enables the eNB to transmit data moreefficiently.

Further, assume that the DSP includes a subframe that is supposed to beused to transmit DSI, other subframes that are used to transmit theother MBMS data packets, and remaining subframes, the eNB may keep mutein the remaining subframes after transmitting the other MBMS datapackets in the DSP. It should be noted that the subframes that form theDSP are subframes of an MCH reserved by the eNB for transmitting MBMSdata packets, and “the eNB may keep mute in the remaining subframes”means that the eNB does not transmit any information on an MCH that isused to transmit MBMS data packets corresponding to the lost type 0control packet group in the remaining subframes.

It is understandable by persons of ordinary skill in the art that theeNB may transmit non-MBMS data packets in the remaining subframes. Thenon-MBMS data packets occupy non-MCHs. For example, the eNB may transmitunicast data packets at low power in the remaining subframes. Theunicast data packets are carried on a DTCH. The occupied transmissionchannel is a DL-SCH.

Step 340: The eNB generates and transmits the DSI corresponding to theDSP.

In this step, the eNB can generate and transmit the DSI according to theprior art. After transmitting a subframe that carries the DSI, the eNBtransmits the received MBMS data packets.

In this embodiment, the eNB may first determine whether data packetsthat are not received meet a given condition. For example, the eNBdetermines whether data packets that are not received by the eNB includea type 0 PDU group corresponding to one or more MBMS data packets. Ifthe given condition is met, the eNB sets a subframe that is used totransmit the DSI corresponding to the DSP to null to prevent the eNBfrom transmitting incorrect DSI which may interfere with other eNBs andcause incorrect data receiving of the UE.

The two subframe processing methods provided by the aforementionedembodiments of the present invention may be combined to form anotherembodiment of the present invention. In the embodiment of the presentinvention, an eNB may first determine whether data packets that are notreceived meet a given condition. That is, the eNB determines whetherdata packets that are not received include two consecutive MBMS datapackets to be scheduled by the eNB in a DSP and a type 0 PDU groupcorresponding to one or more MBMS data packets. The one or more MBMSdata packets may be MBMS data packets that have been or have not beenreceived by the eNB. If the given condition is met, the eNB sets asubframe that is used to transmit DSI corresponding to the DSP to nullto prevent the eNB from transmitting incorrect DSI which may interferewith other eNBs and cause incorrect data receiving of a UE. In theembodiment of the present invention, the method for the eNB todetermining whether data packets that are not received meet the givencondition is the same as the method described in the aforementionedembodiments of the present invention, and is not described here.

In the subframe processing methods provided by the aforementionedembodiments of the present invention, the eNB is an AN device, and theBM-SC is a CN device, but the eNB device and the BM-SC device are notlimited to an AN device and a CN device in embodiments of the presentinvention. For example, the eNB in the aforementioned embodiments of thepresent invention may be replaced by other devices such as a home NodeB(hNB), a microcell NodeB, or other devices on the AN in an LTE+ system;and the BM-SC may be replaced by other devices on the CN.

As shown in FIG. 5, an embodiment of the present invention furtherprovides a subframe processing device, namely, a first device 50, whichis configured to implement the subframe processing methods provided bythe aforementioned embodiments of the present invention. The firstdevice 50 includes a first receiving unit 510 and a first sending unit520. The first receiving unit 510 is configured to determine whetherdata packets that are not received meet a first condition: the datapackets that are not received include at least two consecutive MBMS datapackets to be scheduled by the first sending unit 520 in a DSP. Thefirst sending unit 520 is configured to set a subframe that is used totransmit DSI corresponding to the DSP to null when the determinationresult of the first receiving unit 510 is yes.

“The first sending unit 520 is configured to set a subframe that is usedto transmit DSI corresponding to the DSP to null” may refer to any oneof the following cases: the first sending unit 520 keeps mute in asubframe that is supposed to be used to transmit DSI corresponding tothe DSP; or the first sending unit 520 determines whether to generatecomplete DSI corresponding to the DSP, and if it is determined not togenerate the complete DSI corresponding to the DSP, the first sendingunit 520 keeps mute in a subframe that is supposed to be used totransmit DSI corresponding to the DSP.

In this embodiment, the first receiving unit 510 may be configured toreceive MBMS data packets and determine whether data packets that arenot received meet the first condition according to the received MBMSdata packets. For example, header information of the MBSM data packetsreceived by the first receiving unit 510 includes the total number ofoctets and the total number of packets. The first receiving unit 510determines whether data packets that are not received meet the firstcondition according to the total number of octets and the total numberof packets.

Optionally, in this embodiment, if other MBMS data packets that havebeen received by the first receiving unit 510 and are to be scheduled bythe first sending unit 520 in the DSP exist, optionally, the other MBMSdata packets include any one or more of the following MBMS data packets:MBMS data packets of which time of transmission by the BM-SC is earlierthan the time of transmission of the determined lost consecutive MBMSdata packets by the BM-SC, and which belong to a same service as thedetermined lost consecutive MBMS data packets; and MBMS data packets ofother services that are to be scheduled before the eNB schedules aservice of the determined lost consecutive MBMS data packets. In thelatter case, the other MBMS data packets belong to a service differentfrom that of the lost consecutive MBMS data packets. The time oftransmission of the other MBMS data packets by the BM-SC may not beearlier than the time of transmission of the determined lost consecutiveMBMS data packets by the BM-SC.

Optionally, if a subframe that is supposed to be used to transmit DSIcorresponding to the DSP is a first subframe of the DSP, the othersubframes may be after the subframe that is supposed to be used totransmit DSI corresponding to the DSP. If the subframe that is supposedto be used to transmit DSI corresponding to the DSP is not a firstsubframe of the DSP, the other subframes can be before or after thesubframe that is supposed to be used to transmit DSI corresponding tothe DSP.

Optionally, the first sending unit 520 in this embodiment is furtherconfigured to keep mute in remaining subframes after transmitting theother MBMS data packets. The remaining subframes include subframes thatare after the other subframes in the DSP and reserved for a transmissionchannel that maps a service of the consecutive MBMS data packets by thefirst sending unit 520.

The device according to this embodiment may be a NodeB (such as eNB) orother AN entities, such as an hNB) or microcell NodeB, or a unit that isinside a NodeB or other AN entities. The device may first determinewhether data packets that are not received meet a given condition. Forexample, the device determines whether data packets that are notreceived include at least two consecutive MBMS data packets to bescheduled by the eNB in a DSP. If the given condition is met, the devicesets a subframe that is used to transmit the DSI corresponding to theDSP to null to prevent the device from transmitting incorrect DSI whichmay interfere with other devices and cause incorrect data receiving of aUE.

As shown in FIG. 6, an embodiment of the present invention furtherprovides another subframe processing device, namely, a second device 60,which is configured to implement the subframe processing methodsprovided by the aforementioned embodiments of the present invention. Thesecond device 60 includes a second receiving unit 610 and a secondsending unit 620. The second receiving unit 610 is configured todetermine whether a type 0 control packet group is not received, thatis, the second receiving unit 610 determines whether data packets thatare not received meet a second condition that is the data packets thatare not received include a type 0 control packet group. The secondsending unit 620 is configured to set a subframe that is used totransmit DSI corresponding to a DSP to null, where the DSP is used totransmit MBMS data packets corresponding to the type 0 control packetgroup when the determination result of the second receiving unit 610 isyes.

“The second sending unit 620 is configured to set a subframe that isused to transmit DSI corresponding to the DSP to null” may refer to anyone of the following cases: the second sending unit 620 keeps mute in asubframe, the subframe being supposed to be used to transmit DSIcorresponding to the DSP; or the second sending unit 620 determineswhether to generate complete DSI corresponding to the DSP, and if it isdetermined not to generate the complete DSI corresponding to the DSP,the second sending unit 620 keeps mute in a subframe, the subframe beingsupposed to be used to transmit DSI corresponding to the DSP.

Optionally, in this embodiment, if other MBMS data packets that havebeen received by the second receiving unit 610 and are to be scheduledby the second sending unit 620 in the DSP exist, the second sending unit620 is further configured to transmit the other MBMS data packets inother subframes in the DSP. Optionally, the other MBMS data packets mayinclude MBMS data packets of which time of transmission by the CN deviceBM-SC is earlier than the end time of a synchronization sequencecorresponding to a lost type 0 PDU group; and/or MBMS data packets thatare supposed to be scheduled before scheduling a service of MBMS datapackets corresponding to the lost type 0 PDU group, and which belong toa service different from that of the MBMS data packets corresponding tothe lost type 0 PDU group.

Optionally, if a subframe that is supposed to be used to transmit DSIcorresponding to the DSP is a first subframe of the DSP, the othersubframes may be after the subframe is supposed to be used to transmitDSI corresponding to the DSP. If the subframe is supposed to be used totransmit DSI corresponding to the DSP is not a first subframe of theDSP, the other subframes may be before or after the subframe is supposedto be used to transmit DSI corresponding to the DSP.

Optionally, the second sending unit 620 is further configured to keepmute in remaining subframes after transmitting the other MBMS datapackets. The remaining subframes include subframes that are after theother subframes in the DSP and reserved for a transmission channel thatmaps a service of MBMS data packets corresponding to the type 0 controlpacket group by the eNB.

In the embodiment of the present invention, the type 0 control packetgroup includes all type 0 control packets that include the sameinformation and are transmitted repeatedly.

The device according to this embodiment may be a NodeB (such as eNB) orother AN entities, such as an hNB or microcell NodeB, or a unit that isinside a NodeB or other AN entities. The device may first determinewhether data packets that are not received meet a given condition. Forexample, the device determines whether data packets that are notreceived include a type 0 PDU group corresponding to one or more MBMSdata packets. If the given condition is met, the device sets a subframethat is used to transmit DSI corresponding to the DSP to null to preventthe device from transmitting incorrect DSI which may interfere withother devices and cause incorrect data receiving of a UE.

Persons of ordinary skill in the art may understand that all or part ofthe steps of the methods according to the embodiments of the presentinvention may be implemented by a program instructing relevant hardware.The program may be stored in a computer readable storage medium. Thestorage medium may be a Read-only Memory (ROM)/Random-access Memory(RAM), a magnetic disk or an optical disk.

The above descriptions are merely preferred embodiments of the presentinvention. It should be noted that persons of ordinary skill in the artcan make various improvements and variations without departing from theprinciple of the invention. All such modifications and variations fallwithin the scope of the present invention.

What is claimed is:
 1. A subframe processing method, the methodcomprising: determining, by an evolved NodeB (eNB), that at least twoconsecutive Multimedia Broadcast Multicast Service (MBMS) data packetsto be scheduled in a Dynamic Schedule Period (DSP) have not beenreceived; and setting a first subframe to null, by the eNB, if the eNBcannot determine the transmission position of the at least twoconsecutive MBMS data packets in the DSP, wherein the first subframe isto be used to transmit Dynamic Schedule Information (DSI) correspondingto the DSP, wherein the DSP includes at least the first subframe andsubframes to be used to transmit the at least two consecutive MBMS datapackets that have not been received.
 2. The method according to claim 1,wherein the setting the first subframe to null comprises keeping mute inthe first subframe.
 3. The method according to claim 1, the methodfurther comprising: receiving other MBMS data packets that are to bescheduled in the DSP by the eNB; and transmitting, by the eNB, the otherMBMS data packets in other subframes in the DSP, wherein the other MBMSdata packets comprise at least one of: first MBMS data packets, whereina time of a transmission of the first MBMS data packets by a corenetwork (CN) device is earlier than a time of a transmission ofconsecutive MBMS data packets by the CN device, and the first MBMS datapackets belong to the same service as the consecutive MBMS data packets;and second MBMS data packets, wherein the second MBMS data packets areto be scheduled by the eNB before the eNB schedules a service of theconsecutive MBMS data packets, and the second MBMS data packets belongto a service different from that of the consecutive MBMS data packets.4. The method according to claim 3, wherein, after the eNB transmits theother MBMS data packets, the method further comprises: keeping, by theeNB, mute in remaining subframes, wherein the remaining subframescomprise subframes being after the other subframes in the DSP andreserved for a transmission channel that maps the service of theconsecutive MBMS data packets by the eNB.
 5. A device, comprising: oneor more processors; and a non-transitory computer-readable storagemedium in communication with the one or more processors, with thecomputer-readable storage medium including computer-executableinstructions executed by the one or more processors to: determine atleast two consecutive Multimedia Broadcast Multicast Service (MBMS) datapackets to be scheduled in a Dynamic Schedule Period (DSP) have not beenreceived; and set a first subframe to null if the transmission positionof the at least two consecutive MBMS data packets in the DSP cannot bedetermined, wherein the first subframe is to be used to transmit DynamicSchedule Information (DSI) corresponding to the DSP, wherein the DSPincludes at least the first subframe and subframes to be used totransmit the at least two consecutive MBMS data packets that have notbeen received.
 6. The device according to claim 5, wherein the settingthe first subframe to null comprises keeping mute in the first subframe.7. The device according to claim 5, wherein the one or more processorsfurther execute the computer-executable instructions to: receive otherMBMS data packets that are to be scheduled in the DSP; and transmit theother MBMS data packets in other subframes in the DSP, wherein the otherMBMS data packets comprise at least one of: first MBMS data packetswherein a time of a transmission of the first MBMS data packets by acore network (CN) device is earlier than a time of a transmission ofconsecutive MBMS data packets by the CN device and the first MBMS datapackets belong to the same service as the consecutive MBMS data packets;and second MBMS data packets, wherein the second MBMS data packets areto be scheduled before the device schedules a service of the consecutiveMBMS data packets and the second MBMS data packets belong to a servicedifferent from that of the consecutive MBMS data packets.
 8. The deviceaccording to claim 7, wherein, after the transmitting the other MBMSdata packets in other subframes in the DSP, the one or more processorsfurther execute the computer-executable instructions to: keep mute inremaining subframes, wherein the remaining subframes comprise subframesafter the other subframes in the DSP and reserved for a transmissionchannel that maps the service of the consecutive MBMS data packets.